Item 1A. Risk Factors.

Other than the risk factors listed below, there have been no material updates during the period covered by this Form 10-Q to the Risk Factors as set forth in Item 1A. of our Annual Report on Form 10-K for the year ended December 31, 2020. These risks and uncertainties, however, are not the only risks and uncertainties that we face. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial may also significantly impact us. Any of these risks and uncertainties may materially and adversely affect our business, financial condition or results of operations, liquidity and cash flows.

​

Risks Relating to Legal and Regulatory Matters

​

If one or more of the index providers from which we have licenses or service providers with respect to proprietary products fails to maintain the quality and integrity of their indices or fails to perform under our agreements with them or if customer preferences change, or if we fail to maintain the quality and integrity of our proprietary indices**, revenues we generate from trading in these proprietary products or the calculation and dissemination of index values may suffer.**

We are a party to a number of license agreements pursuant to which we may list for trading products based on various indices including pursuant to license agreements that we have with S&P, Dow Jones, LSEG and MSCI. These license agreements authorize us to list products based on a number of indices, and some of the resulting index options and futures are among the most actively traded products on our exchanges. We also enter into licensing agreements pursuant to which we calculate and disseminate values of proprietary indices. We believe that demand for our products is based in part on market perception of the quality and integrity of these indices. The quality and integrity of each of these indices are dependent on the ability of the index providers, including us, to maintain the index, including by means of the calculation and rebalancing of the index, and are dependent on the index providers for a number of things, including the provision of index data. We also rely on index providers to enforce intellectual property rights against unlicensed uses of the indices and uses of the indices that infringe on our licenses. Furthermore, some of our agreements concerning our proprietary products provide for the parties to those agreements to provide important services to us. If any of our index providers, including us, are unable to maintain the quality and integrity of their indices, or if any of the index providers or service providers fail to perform their obligations under the agreements, trading in these products, and therefore transaction fees we receive, may be materially adversely affected or we may not receive the financial benefits of the agreements that we negotiated.

​

We have in the past discovered instances, and we may in the future discover instances, where the spot Cboe Volatility Index (“VIX Index”) calculation differs from the calculation described in the VIX White Paper, which details the formula used for deriving values related to the VIX Index, including those instances that we announced on July 30, 2021. In those certain instances, the calculation of the spot VIX Index was not possible, resulting in the republication of the last published spot VIX Index value. In addition, from time to time we have in the past also discovered issues, and we may in the future discover issues, in the spot VIX Index calculation, such as incorrectly zeroing-out market quotes in the calculation of the spot VIX Index. Differences in the calculations or incorrect calculations of spot VIX Index values or our other spot volatility indices or the failure to implement any planned changes may result in the loss of perceived quality and integrity of our indices, loss of demand for our products, increased potential for investigations and enforcement proceedings, and increased exposure to third party claims and related litigation expenses, which could have a material adverse effect on our business, financial condition and operating results.

​

Changes in the tax laws and regulations affecting us, our products and our market participants could have a material adverse effect on our business.

Legislation may be proposed, both domestically and internationally, that could add a transaction tax on our products or change the way that our market participants are taxed on the products they trade on our markets. More recently, a number of federal, state and local jurisdictions in the U.S. and EU Member States have considered a financial transaction

tax, but many details remain to be discussed and agreed, including how to assess the tax. Additionally, the proposed Modernization of Derivatives Tax Act of 2021 would introduce in the U.S. mark-to-market tax treatment for all derivatives contracts and require gains and losses be taxed at ordinary income tax rates. If such proposals were to become law, they could have a negative impact on the securities industry and on us by making transactions more costly to market participants, which may impact derivatives trading behavior, reduce trading or clearing and could make our markets less competitive, and they could result in a reduction in volumes and liquidity, which would have a negative impact on our operations.

In addition to proposed tax changes that could affect our market participants, like other corporations, we are subject to taxes at federal, state and local levels, as well as in non-U.S. jurisdictions. Changes in tax laws, regulations or policies or successful claims by tax authorities could result in our having to pay higher taxes, which would in turn reduce our net income. If this occurs, we may experience a higher effective tax rate.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds.

Share repurchase program

In 2011, the board of directors approved an initial authorization for the Company to repurchase shares of its outstanding common stock of $100 million and approved additional authorizations of $100 million in each of 2012, 2013, 2014, 2015 and 2016, $250 million in each of 2018, 2019 and 2020, and $200 million in February 2021, for a total authorization of $1.6 billion. The program permits the Company to purchase shares through a variety of methods, including in the open market or through privately negotiated transactions, in accordance with applicable securities laws. It does not obligate the Company to make any repurchases at any specific time or situation. The Company did not repurchase shares of its common stock under its share repurchase program during the third quarter of 2021 and had $318.9 million of availability remaining under its existing share repurchase authorizations as of September 30, 2021.

Purchase of common stock from employees

The table below reflects the acquisition of common stock by the Company in the three months ended September 30, 2021 that were not part of the publicly announced share repurchase authorization. These shares consisted of shares retained to cover payroll withholding taxes in connection with the vesting of restricted stock unit awards and performance share awards.

​

Use of Proceeds

None.

Item 3. Defaults upon Senior Securities.

None.

Item 4. Mine Safety Disclosures.

Not applicable.